27 апреля (пятница)  в 17 часов в 610 аудитории состоится семинар кафедры алгебры и математической логики.

Докладчик:  
Dino Rossegger (Institute of discrete mathematics and geometry, Vienna University of Technology) “Computable structure theory with respect to equivalence relations”

Abstract:

Degree spectra of structures and computable categoricity are two of the best studied notions in computable structure theory. The aim of the two notions is to answer the following questions:

1. Which families of Turing degrees can be realized as degrees of isomorphic copies of a structure?

2. Given a computable structure, how hard is it to compute isomorphism between it and other computable copies?

In my research I studied these questions with respect to other equivalence relations than isomorphism: How hard is it to compute embeddings between bi-embeddable computable structures? And which families of degrees are realized by bi-embeddable or elementary bi-embeddable copies of a structures?

In my talk I will discuss these questions and present additional results on Scott sentences of linear orderings and computable transformations of classes of structures.